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Show 333 excelled in size the three from California. The southern series represents the so- called M. varians of Gray and Baird. The unsatisfactory character of the several species of North American Skunks of the mephitica group, and the wide range of color- variation among individuals from the same locality, I have previously had occasion to notice,* and a re- examination of the subject confirms the conclusions then announced, which, I am happy to find, have recently received the support of Dr. Goues, who has lately made a study of this group. t As Dr. Goues has remarked, and as the subjoined measurements show, few species of animals vary so much in size and in cranial characters as the present, independently even of sex and age. Some specimens are not only more than one- fourth larger than others, but " there is a corresponding range of variation in contour. Compared with an ordinary ratio of osteological variability," says Dr. Coues, " the discrepancies are almost on a par with those exhibited by the coloration of the animal when set over against the more constant markings of most animals." In view of this great degree of variability, however, Dr. Goues has ventured to describe a " new species" ( M. frontata), based on a fossil skull from one of the bone- caves of Pennsylvania, as it seems to me, unadvisedly. The specimen, though that of a very aged individual, is scarcely larger ( see subjoined table) than the average of specimens from the Eastern States, its chief difterence from the average skull consisting in an abnormal tumidity of the frontal region, arising evidently from disease. It is a feature by no means confined to the present example, but is merely an extreme enlargement of the sinuses of the frontal region often seen in specimens of the existing animal, evidently resulting from disease. In No. 917 ( Albany, N. T.), No. 8099 ( Fort Cobb, lnd. T.), No. 1878 ( Calcasieu Pass, La.), and No. 1620 ( Indianola, Tex.), the same tendency is strongly marked, which, in some of these • specimens, had they attained equal age, must have resulted in a malformation nearly or quite as great as is seen in the fossil skull in question. In this connection, I may add that a pretty careful examination of the fossil remains of Carnivoray collected by Professor Baird many years sinoe from the bone- caves of Pennsylvania ( of which this fossil skull of the Skunk forms a part), has failed to show any of them to be specifically different from the species now or recently living in the same region. Many of them are remains of individuals of large size, but not exceeding the dimensions of specimens of the recent animal from the same or contiguous regions. These remains include, among others, the following species:- Lynx rufus, Urocyon virginianus, Mustela pennanti, Mustela americana, Putorius vison, Lutra canadensis, Mephitis mephitica ( other specimens than the " frontata " skull), Procyon lotor, Ursus americanus, etc. # See Ball. MUB. Coinp. Zool., vol. i, pp. 178- 181, Oct., 1869. t BuU. U. S. Geol. and Geog. Snrv. or the Territories, vol. i, No. 1, pp. 7- 15, 1875. |